Nail and like magazines

ABSTRACT

There is described feed mechanism for a pneumatic fastener gun, in which an actuator is adapted to contact the surface of the workpiece and thus to operate the intermittent feed of nails which are assembled like a belt and stored in a magazine.

United States Patent Malcolm Edwin Hillier [72] Inventor Deal. England [21 Appl. No. 687,853

[22] Filed Dec. 4, 1967 [45] Patented Jan. 26, 1971 [73] Assignee Gaston E. Marbaix Limited Basingstoke, England a British company [32] Priority Dec. 7, 1966 33] Great Britain [54] NAIL AND LIKE MAGAZINES 13 Claims, 10 Drawing Figs.

[52] U.S. Cl 227/7, 227/136 [51] Int. Cl 827i 7/06 [50] Field of Search 227/5, 6, 7, 8,95,114,115,116,135,126,138

[56] References Cited UNITED STATES PATENTS 2,653,316 9/1953 Beckman et a1.

3,259,292 7/1966 Maynard 227/136X 3,281,046 10/1966 Boulay 227/115 3,330,462 7/1967 Colechia et al. 227/136 Primary Examiner-GranvilleY. Custer, Jr. Attorney-Shapiro and Shapiro ABSTRACT: There is described feed mechanism for a pneumatic fastener gun, in which an actuator is adapted to contact the surface of the workpiece and thus to operate the intermittent feed of nails which are assembled like a belt and stored in a magazine.

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NAIL AND use MAGAZINES This invention relates to nail and like magazines and more particularly to such magazines for pneumatic nailing and like machines known as fastener guns.

The term nail and like' is intended to cover the general category of devices which, like nails, can be used for joining two objects together by penetrating both objects. Such devices include nails, pins, staples, corrugated fasteners, etc. These devices will hereinafter be referred to in this specification as nails. The term firing" is used colloquially in relation to pneumatic fastening machines which drive fasteners by the impact of a socalled blade, as meaning the actual operation of driving a fastener; it is, of course, analogous to firing a gun, but the machines we are concerned with have nothing to do with firearms.

The magazines for fastener guns in the past have generally taken a form somewhat akin to that of the common office staplers, i.e. they contain a plurality of nails joined together or touching edgewise in a line so orientated as to present the nails in the machine in a position in which no further orientation is necessary. This has proved satisfactory in the case of small nails, but where larger nails are to be used, say for example four inch roundheaded nails, the length of such magazines become unwieldy or insufficient nails can be accommodated to make the gun operation practical.

The present invention, therefore, seeks to provide a nail and like magazine which will obviate or substantially reduce the disadvantages in the above described straight" magazines, and also to provide effective and safe feed mechanism in a fastener gun; and arrangements which are particularly well adapted for use in guns which are fed from detachable magazines operating on the belt" principle.

It will, of course, be appreciated that while the greatest advantages of the present invention lie in the use of large nails, the invention is equally applicable to smaller sizes. Staples and corrugated fasteners will require some adaption of the arrangements proposed herein; for example, staples may be interattached by one limb only to their neighbors or they may have both limbs attached, each to an adjacent limb of neighbors. For brevity, the word nail herein (except where otherwise required by the context) is intended to include staples, corrugated fasteners, or pins.

According to the invention there are provided in (including as an attachment to) a pneumatic fastener gun, means for feeding nails for firing into a surface one at a time into the firing location (which may be considered analogous to the breech of a gun) which means are operated by an actuator which is itself moved by movement of the gun towards and away from the surface. The nail-feeding mechanism is therefore operated somewhat in the same manner as the bump valves (as they are called) of earlier fastener guns by the act of placing the gun upon the surface of the workpiece and removing it therefrom for the next firing.

Further according to the invention, there are provided in (or for attachment to) a pneumatic fastener gun, means for feeding nails one at a time for firing into a surface into the firing location comprising a pawl arranged so as to engage the foremost nail of an interconnected belt of nails and to be urged by a spring to move that nail into the firing location, and actuator means to move the pawl out of said engagement and ready it for a subsequent engagement, and to load the spring to enable it to perform a further movement which actuator means are operated by positioning the gun against the said surface.

The invention is preferably applied in cases in which the nails are interattached to form a belt (analogous to a belt of cartridges) which is to fed into the firing location one nail at a time. Where so applied, the invention preferably includes provision such that the foremost nail of the belt and the nail next thereto are both engaged by pawls to urge them towards the firing position, both pawls being moved simultaneously for reengagement with nails as a result of movement of the gun towards and away from the surface of the workpiece.

The operation of the feed mechanism is preferably associated with that of a bump valve of the gun, and the actuator, which makes working contact with the surface is preferably restored to the position which corresponds to removal of the gun from the surface by pneumatic pressure acting on the bump valve (as in US. Pat. No. 3,043,272, granted July I0, 1962, or US Pat. No. 3,152,5l9, granted Oct. 13, I964). This and further features of the invention as defined by the claims, will be made more apparent from the description which follows of tow examples of the invention, the first example being a simplified version which may be adequate for use with some guns, and the second example being a more elaborate and sophisticated version, probably more suitable for use with a gun designed to use it, and such gun being probably (but not necessarily) a heavy-duty implement for such nails as roundheaded four inch nails.

In the accompanying drawings:

FIG. I is a side view of the first example of feed mechanism according to the invention.

FIG. 2 is a sectional view on line I 1-1 1 of FIG. 1.

FIG. 3 is a schematic plan view of the magazine of FIG. I.

FIG. 4 is a side view illustrating the second example in idle position.

FIG. 5 shows the same in fixed position immediately after firing.

FIG. 6 illustrates similarly how the gun is loaded and also how a safety device operates to prevent firing when the gun is empty or jammed.

FIG. 7 is a part-sectional plan view illustrating the feed pawls when the gun is as shown in FIG. 4.

FIG. 8 shows the pawls when the gun is as shown in FIG. 5.

Fig. 9 illustrates inplan the magazine and feed chute indicating an imaginary position of nails.

FIG. 10 illustrates a modification of a detail of FIG. 9.

Referring to FIGS. 1, 2 and 3 of the drawings, a magazine for a pneumatic fastener gun is constituted by a receptacle 1 of circular section in which a row 2 of parallel nails 3 interattached in beltlike manner can be placed, bunched or rolled in spiral fashion as is shown in FIG. 3. The nails are fed along a guideway or chute 4 past the feeding mechanism 5 at the forward end of the guideway. The receptacle 1 has a conical floor, as shown at 1A and the spiral belt therefore reposes somewhat helically.

The feeding mechanism 5 comprises two pins which are in effect pawls 6, being resiliently urged by leaf springs 7 into the path of the chute, the pawls being mounted on a bar 8 which is in turn pivotally mounted at- 15 on bellcrank 9 pivotally mounted on the exterior of the chute at 10. The bellcrank 9 is the actuator of the feed mechanism. The bar 8 is mounted for reciprocation in a direction parallel to that of the chute 4, and is guided by a pair of telescopic guides consisting of rods 12 in guide sleeves 13. The bar 8 is urged forwardly (to the left in FIG. 1) by a telescopic compression spring unit 14. The bellcrank 9 has a downwardly extending tail 16 having a roller 17 at the end thereof, for engagement with the surface of the workpiece which is, for example, a plank of wood. The foremost nail (indicated at 11) is shown in the firing location ready to be struck by the blade of the gun (not shown).

In operation of the feeding mechanism, the pawls 6 engage behind the foremost nail and are urged forward (i.e. to the left) by the spring mechanism 14 to push this nail to the firing location whence it will be hammered into the workpiece by the blade of the gun. As the gun is lowered into contact with the workpiece, the roller 17 engages the surface of the workpiece and pushes the tail l6 upwardly to swing the bellcrank or actuator 9. This pivotal movement of the bellcrank 9 brings the bar 8 backwards (i.e. to the right in FIG. I); the pawls 6 being resiliently mounted, ride over the next to foremost nail, and engage behind it. When the gun is lifted from the workpiece, the bellcrank 9 is released and the spring mechanism 14 moves the bar 8 forward again to feed the next nail; the remainder of the belt is, of course, thus pulled forward to the extent of the pitch distance of the nails.

In order to facilitate the riding of the pawls 6 over the nail on the return stroke, the pawls are beveled to one side, so that the resultant force due to the nail pushes the pawls out against the springs 7.

Means are also provided for preventing backward movement of the belt of nails during the return stroke of the feeding mechanism 5, which might occur when the receptacle 1 is nearly empty. This consists of a pair of pins 20 forming in effect spring detents. The pins 20 are beveled towards the rear and are urged inwards by leaf spring 21 on the side of the chute 4 opposite to the side on which are the pawls 6. Thus, as the nails move forward, they push the pins 20 out of the way as a result of their bevel, but after each nail has passed, the pins spring back behind it to prevent any backward motion of the nails. The pins 20 are positioned in the same transverse plane as the pawls 6 when the latter are in the forward position. Pivotal latches may be substituted for the sliding pins.

According to a further feature of the invention the whole magazine and feeding mechanism above described is arranged as a unit which is attachable to the gun by a removable pivot pin at 21, the unit being held in working position by a releasable spring catch 22. The unit is either opened for reloading by releasing the catch 22 and swinging the gun (anticlockwise as seen in FIG. 1) or it may be removed and replaced by another, simply by releasing the catch 22 and disengaging the pin 21.

Turning now to the remaining FIGS. of the drawings, the second and more elaborate example of the invention is illustrated. To distinguish clearly from the first example, different reference numerals will be used.

The gun itself is indicated generally at 40, and has a handgrip 41, trigger 42, protruding bump valve stem 43 and indicated in broken line, a working blade 44 of which the available stroke is at least as long as the nails used. The gun 40 itself is attached by a pivot pin 45 to the feed and magazine unit generally indicated by 46. A releasable catch is provided to attach the rear (or right-hand in the drawings) end of the unit 46 to the grip 41, or any other convenient attachment may be provided which normally locks the unit 46 to the gun 40 and can be unlocked for replenishing the magazine. Such a catch is illustrated in FIG. 4.

In FIG. 9 is seen the arrangement of the magazine; this may be, or be arranged to contain, a disposable container. As shown, it is occupied by a belt of roundheaded nails 47 (seen better in FIG. 6) with heads 47A. Such a belt consists of parallel nails 47 interattached by pliable ligaments 48 of tapelike nature. The container body forms the actual magazine for the belt of nails; it has an outlet chute formed by a floor 50, a wall 51, and (in the version of FIG. 9) a spring 52 which normally holds the belt lightly against the wall 51 and which has a frictional detent bend in it at 52A, to engage between two adjacent nails to restrain the belt from loose disorder. In the alternative of FIG. 10, the wall 51 carries a leaf spring 53 of which the end 54 can engage behind each successive nail 47 of the belt, the spring 53 being moved out of the path of the belt each time a nail passes the end 54 which can therefore be regarded as a detent or ratchet pawl. As is indicated in FIG. 6, the belt of nails is loaded into the magazine 49, for example as a bunched up zigzag arrangement with its forward end consisting of say nine nails lying in the chute, against the wall 51. The magazine and chute so constituted may be removable as a whole from the remainder of the unit 46, in which case they may be disposable; or the magazine may be locked by putting into it a pack comprising the belt of nails in a disposable container. It will be understood from FIG. 6 that the reloading operation is preformed by swinging the unit 40 about the pivot 45, to expose the top of the magazine and chute. There may be provided a hinged lid to cover the magazine, as indicated at 54.

The forward part of the unit 46, i.e. that which is directly pivotally attached (at 45) to the gun, is a structure comprising a guide part 55 (see FIGS. 7 and?!) which, complementary to wall 51, forms part of the feed chute for the nail belt. The guide 55 leads into the firing location, which can conveniently be termed the breech, at 56. This is a channel of basically circular section corresponding in diameter to the nail heads 47A (see in particular FIGS. 7 and 8) the channel being open to the right of the drawings to admit the nails and having a short limb 57 extending towards the magazine. This limb 57 slidably supports two spring-loaded chamfered detents 58; these are arranged to ride over each advancing nail and engage behind it to prevent it moving backwards, as shown in FIGS. 7 and 8.

The structure of the unit 46 also supports, on a pivot 59, a bellcrank lever 60 with a tail 60A. The lever 60 slidably supports two pawls 61, 62, which are urged inwards by leaf springs 63, so that their chamfered inner ends 61A, 62A, ride over and unidirectionally engage the nails. The pawls 61, 62 are spaced correspondingly to the pitch distance of the nails in the belt, so that 61 engages behind the foremost nail and 62 the next successor.

Four guiding rollers 64 in two pairs are supported by the structure of unit 46. Between them is moveable up and down and somewhat inclined (as seen in FIGS. 4 to 6) an actuator element 65. This has a radiused nose 65A to contact the surface of the workpiece, so that when the gun as a whole is placed on the surface and moved into contact therewith, the actuator 65 is pushed relatively upwards. The down position is shown in FIGS. 4 and 6; the up position in FIG. 5. The bottom of the unit 46 preferably has a pair of ridges 67, one on each side of the breech, which ridges define the actual distance from the surface of the gun as a whole.

The top end of the actuator 65 (preferably having a durable low-friction pad 658 for example of hardened steel) is arranged so that when the gun is operative, it bears against the bump valve stem 43. Consequently (see FIGS. 4 and 5) when the actuator 65 is up, it raises the bump valve thus conditioning the gun for firing by the trigger 42. With some types of gun, if the trigger 42 be held pulled, the gun will operate merely by being lowered on to the workpiece surface; this is equally possible when the present device is used. Note that, as is usual, the bump valve stem is pushed downwards by the working air pressure in the gun; therefore, when the whole gun of FIG. 4 is raised off the surface, the valve stem 43 pushes the actuator down (to the condition of FIG. 4).

The actuator 65 has projecting from it a pin 66, which is unidirectionally (downwardly) engaged by the tail 60A of the bellcrank lever 60. Thus when the actuator 65 is raised as in FIG. 5 it swings lever 60 anticlockwise. This moves the pawls 61, 62, rearwards to engage a new pair of nails. The lever 60 is connected by a tension spring 67 which at one end is attached to the bar and at the other end to the unit 40, the spring 67 being offset from the pivot 45. Thus, when the gun assembly is opened for leading (FIG. 6) the spring 67 is relaxed, whilst in the ready for use" condition (FIGS. 4 and 5) the spring is prestrained (see difference in its length between FIGS. 4 and 5). When the pin 66 moves down with the actuator 65, the spring 67 acts to pull lever 60 clockwise. Thus, when the foremost nail of the belt is free to enter the breech 56, the spring 67 operates to pull the foremost nail, its successor, and therefore the belt in the chute, forward via the pawls 61, 62 (whilst the detent 58, and the light spring 52 or 53, yield to allow the nails to pass).

The movement of the foremost nail into the breech is prevented after firing has been initiated, because that nail contacts the blade 44. Therefore, the nail can only be advanced by the spring 67 after the blade 44 has virtually completed its idle (upward) stroke.

As a precautionary and user-aid device, there is formed on the lever 60 a catch at 608 (for clarity referenced only in FIG. 6). The structure pivotally supports a latch 69 which is spring loaded anticlockwise, i.e. in the sense to cause the latch to engage the catch 60B. The positioning of these parts is such that, if the lever 60 moves further clockwise than it can when there is a nail in the breechthat is to say, if the nails have all been expended and'the gun is empty as in FIG. 6 or if some failure has prevented the feed of a nail into the breechthat the latch 69 engages the catch 60B, locking the lever 60 against further movement and via pin 66 locking the actuator 65 down, and therefore preventing opening of the bump valve. Thus the gun cannot be fired when empty, in which condition the act of firing might be damaging to the mechanism. When the gun has been reloaded, or when a stoppage has been cleared, the latch 60B is released by hand. Its function 'is, therefore, both precautionary (by preventing firing empty) and indicative, in that the locking of the parts tells the user that the gun is empty or jammed.

Spring detents 70 may be provided to lock in position the magazine assembly when this is made detachable, as is preferred. These detents may, for example, engage apertures in a short plate 71 which extends from the container 49.

The invention is proposed to be applied in conjunction with that which is disclosed in my copending application Ser. No. 603,256, filed Dec. 20, 1966, now US. Pat. No. 3,479,926, issued Nov. 25, 1969.

1 claim: v

1. In a fastener gun for driving nails into a surface, means for feeding the foremost nail of a belt of interconnected nails to a location of the gun at which nails are driven, a pawl arranged so as to engage the foremost nail, means for moving said pawl in one sense of direction and thereby to move said foremost nail toward said location, and actuator means adapted to be moved by the positioning of the gun against the surface and mechanically to transmit resultant movement to the pawl in the opposite sense of direction for engaging the pawl with the next nail, whereby the nails are fed in steps, one at a time, said actuator means being energized entirely in response to movements of the gun toward and away from the surface.

2. in a gun according to claim 1, said feeding means being adapted to feed the nails in coplanar fashion to said location, and said means for moving said pawl being adapted to move the pawl in the plane of the nails.

3. In a gun according to claim 1, said means for moving said pawl in one sense of direction comprising a spring.

4. ln a gun according to claim 1, there being a second pawl arranged to engage the nail behind the foremost nail and being coupled to the first-mentioned pawl for movement therewith.

5. In a gun according to claim 4, said pawls being supported upon a pivoted lever, and there being a unidirectional connection between said lever and the actuator means, and further comprising spring-urged detent means for engaging a nail of the belt to prevent reverse movement thereof.

6. In a gun according to claim 1, said pawl being duplicated so that two pawls engage the foremost nail at points spaced along the length thereof.

7. in a gun according to claim 1, said gun having a bump valve and means for operating the bump valve from said actuator means.

8. In a gun according to claim 7, said bump valve being adapted to move outward from the gun by air pressure applied to the gun and being adapted to move said actuator means outward from the gun.

9. ln a gun according to claim 1, said pawl being carried by a lever and said means for moving said pawl in one sense of direction comprising a spring for moving said lever, said gun further comprising a spring-urged detent adapted to lock said lever against movement whenever the lever moves to a position corresponding to emptiness of the gun.

10. in a gun according to claim 9, said spring-urged detent also being adapted to lock said actuator means.

11. in a gun according to claim 1, a magazine adapted to contain said nails and deliver the same to said feeding means.

12. In a gun according to claim 11, said feeding means and said magazine being pivotally connected to the gun and said magazine having a belt container adapted to be made accessible for loading by swinging of the magazine and feeding means relative to the gun about the said connection.

13. In a gun according to claim 12, said means for moving said pawl in one sense of direction comprising a tension spring anchored to the gun and offset from said pivot connection so as to be relaxed or tensed by the said swinging. 

1. In a fastener gun for driving nails into a surface, means for feeding the foremost nail of a belt of interconnected nails to a location of the gun at which nails are driven, a pawl arranged so as to engage the foremost nail, means for moving said pawl in one sense of direction and thereby to move said foremost nail toward said location, and actuator means adapted to be moved by the positioning of the gun against the surface and mechanically to transmit resultant movement to the pawl in the opposite sense of direction for engaging the pawl with the next nail, whereby the nails are fed in steps, one at a time, said actuator means being energized entirely in response to movements of the gun toward and away from the surface.
 2. In a gun according to claim 1, said feeding means being adapted to feed the nails in coplanar fashion to said location, and said means for moving said pawl being adapted to move the pawl in the plane of the nails.
 3. In a gun according to claim 1, said means for moving said pawl in one sense of direction comprising a spring.
 4. In a gun aCcording to claim 1, there being a second pawl arranged to engage the nail behind the foremost nail and being coupled to the first-mentioned pawl for movement therewith.
 5. In a gun according to claim 4, said pawls being supported upon a pivoted lever, and there being a unidirectional connection between said lever and the actuator means, and further comprising spring-urged detent means for engaging a nail of the belt to prevent reverse movement thereof.
 6. In a gun according to claim 1, said pawl being duplicated so that two pawls engage the foremost nail at points spaced along the length thereof.
 7. In a gun according to claim 1, said gun having a bump valve and means for operating the bump valve from said actuator means.
 8. In a gun according to claim 7, said bump valve being adapted to move outward from the gun by air pressure applied to the gun and being adapted to move said actuator means outward from the gun.
 9. In a gun according to claim 1, said pawl being carried by a lever and said means for moving said pawl in one sense of direction comprising a spring for moving said lever, said gun further comprising a spring-urged detent adapted to lock said lever against movement whenever the lever moves to a position corresponding to emptiness of the gun.
 10. In a gun according to claim 9, said spring-urged detent also being adapted to lock said actuator means.
 11. In a gun according to claim 1, a magazine adapted to contain said nails and deliver the same to said feeding means.
 12. In a gun according to claim 11, said feeding means and said magazine being pivotally connected to the gun and said magazine having a belt container adapted to be made accessible for loading by swinging of the magazine and feeding means relative to the gun about the said connection.
 13. In a gun according to claim 12, said means for moving said pawl in one sense of direction comprising a tension spring anchored to the gun and offset from said pivot connection so as to be relaxed or tensed by the said swinging. 